Door operating device



May 7,1935. H. GROSS 2,000,515

DOOR OPERATING DEVICE Filed March 21, 1932 4 Sheets-Sheet 1 INVENTOR.

;' By M A T TORN E Yv L.H.GROSS DOOR OPERATING DEVICE Filed March 21, 1932 May 7, 1935.

4 Sheets-Sheet 2 LEO H Gkoss ATTORNEY.

y 7, 1935- L. H. GROSS 2,000,515

DOOR OPERAT ING DEVICE Filed March 21, 1952 4 Sheets-Sheet 3 I N V EN TOR.

A TTORNEY May 7, 1935. L GROSS 2,000,515

DOOR OPERATING DEVICE Filed March 21, 1932 4 Sheets-Sheet 4 IN V EN 'I'UR.

45 [0 GROSS BY L\\ 13$ MW ATTORNEY Patented May 7, 1935 UNITED STATES PATENT OFFICE Application March 21,

9 Claims.

This invention relates to improvements in door operating devices, and more particularly to a power operator for doors of garages and like structures wherein it may be desirable to control a door operator by remote control means.

An object of this invention, generally speaking, consists in the provision of a more economically manufactured, and more simple and rugged device, than those heretofore offered to the trade for kindred purposes.

Another object of the invention is attained in the construction of a power door operator employing cables or like tension elements to constitute the major connections between a compact, simplifled operating unit, and the doors to be controlled.

A further object of the invention is attained in an improved, simplified operating assembly which may be installed and removed as a complete unit, and the parts of which are readily accessible for purposes of repair or routine attention, such as lubrication and adjustment.

A further object of the invention is attained in a device of the type and for the purpose noted, which may be constructed, for the most part, of standard stock materials, requiring a minimum of machine work and special fabrication.

Additional objects of the invention, as exemplified in the following description, will be noted in the ready adaptability of the structure, without change in the operating unit thereof, to doors of a wide variety of types, for example, doors of outwardly swinging type, doors of in wardly swinging type, folding doors, andoverhead doors.

Still further objects may be noted in the provision of an improved, simplified arrangement of the electric circuit arrangement of the power operator; the provision of an improved design of vehicle-actuated switch adapted for installation for example, in a driveway leading to a garage.

Further objects and advantages of the invention will appear as the description proceeds, and from the accompanying drawings forming a part a of this specification, and in which:

Fig. l is a horizontal sectional elevation of the device of my invention as applied to paired, outwardly swinging garage doors; Fig. 2 is an ar rangement of the parts of my device as employed for the operation of inwardly swinging doors, and

being a horizontal sectional elevation thereof;

Fig. 3 is a horizontal sectional elevation, as viewed when looking upwardly frombelow the operating unit, and illustrating one manner in which the device may be applied for the operation of 1932, Serial No. 600,148

doors of so-called overhead type; Fig. 4 is a vertical sectional elevation of the structure shown in Fig. 3; Fig. 5 is a side elevation, showing a preferred form of the power operator; Fig. 6 is a top plan view of the assembly shown in Fig. 5; Fig. 7 is a side elevation of a safety release device, preferably employed with or constituting a part of the driving unit illustrated in Figs. 5 and 6; Fig. 8 is a top or plan view of a switch assembly preferably employed in connection with the mechanism of Figs. 5 and 6; Fig. 9 is a sectional elevation showing a release clutch, preferably employed only in an emergency to enable manual operation of the doors with which the power operator is associated; Fig. 10 is a wiring diagram illustrating the preferred circuit relation existing between the power operator and the several control switches therefor, and Fig. 11 is a vertical sectional elevation illustrating a preferred form of vehicle-actuated switch adapted to be installed,

for example, in a driveway, to enable appropriate circuit control of the mechanism of the present invention when employed in connection with garage doors.

Referring now by. characters of reference to the drawings, Fig. 1 shows a fragmentary portion of a structure such as a garage, provided with side walls 15, an upper front wall l6, outwardly opening doors I! and I8, hinged as at l9 to the front wall I6, of the structure. Arms or brackets 20 fixedly secured to the inside of walls 15, serve to carry pivots 2|, about which are rotatably or swingably mounted, a pair of arms 22, provided at their outer ends with upstanding pivot pins 23, serving to engage the corresponding inner ends of arms 24, one of which is provided for each of the outwardly swinging doors. The outermost ends of arm 24 are in turn pivoted, as at 25. to fixed pivot brackets 26, projecting inwardly of the doors I! and I8'. As appears in Fig. l, the brackets 20 and 26 may be provided with a plurality of aligned pivot-receiving openings, to permit an adjustment of the range of door movement. In the construction described the power operator, including a double reel portion, hereinafter referred to, serves to actuate, concurrently in the same direction, a pair of cables or equivalent tension elements 21, one end of each of which is secured to a pivot 23 and hence also to the adjacent extremities of arms 22 and 24. Tensioned always in a direction opposite to that of elements 21, are a pair of cable elements 28, extending, in Fig. 1, each through a pair of spaced pulleys 29, which may be mounted as shown, on the inside of wall l5, and at about the height of brackets 20.

It will appear that as cables 21 are concurrently tensioned the arms 22 and 24 will be swung outwardly toward the front of the building, and in a direction to move the doors I1 and I8, concurrently, toward open position. Obviously, when the cables 28 are tensioned and the cables 21 correspondingly paid out, as later appears, the paired arms 22 and 24 will be moved in the opposite direction, or so as to bring the doors H and I8 first toward, and then into closed position.

In Fig. 2 there prevails an arrangement closely akin to that of Fig. 1 except that the arrangement of inwardly swinging doors dispenses with the necessity of arms 22 and 24; upstanding pivots or pins 23 being carried directly by the doors I! and I8, preferably near their outer extremities, and on the rear face of each door. The operation of this construction is, in principle, the same as that of the structure of Fig. 1 except that the tensioning of cables 21, serves, in Fig. 2, to move the doors toward closed, rather than toward open position. The same operating unit, indicated generally at 30, may be employed in both cases.

In Fig. 3 is shown a further slight modification of the arrangement of cables, as adapted to the operation of door of overhead type. In this construction the same operator 30 may be employed. The overhead door shown at 3| is in a partly open position. As well understood in the art, doors of this type usually operate in lateral guides 32 and 33, the uppermost portions of which are disposed in a substantially horizontal plane, and the lowermost portions of which lie in a vertical plane, the latter portions serving to receive the door proper 3|, when in closed position. Doors of this type may, as usual, be counterweighted or counterbalanced to facilitate their movement between closed and open positions. Doors of this type are usually formed of a series of transversely hinged sections such as 34, the hinge line therebetween being indicated at 35. In this structure, as before, cables 21 and 28 are arranged to be selectively tensioned by the power element 30. The cables 21 and 28 may, as preferred, each consist of a single length of the flexible tension element, anchored say at 36, near the upper margin of the door. The cable anchorage 36 may conveniently consist of an eye member pivoted for movement about an axis in the plane of the door.

It will appear that, for example, when the cable 21 is tensioned, and the cable 28' reeled out, the door 3| will be moved toward the wall l6, and hence toward its closed position. Conversely, when the cable 28 is tensioned, the door will be moved upwardly to an extent where it will be disposed entirely in the horizontal portions of the guides, and thus brought fully to open position.

Proceeding now to a description of the power operating unit, this is shown as a self-contained structure, the base portion or upper deck of which is indicated at 31, the lower deck 38 being suspended therefrom as by spacers 39. Mounted upon the base 31, is a motor 40 which may be either of A. C. or D. C. type, provided with a hollow driving hub 4| secured as by a. set screw, to the motor shaft proper. Disposed in endwise movable relation within the hub 4|, is a worm shaft 42, carrying a driving worm 43 and provided with an outboard bearing 44. The worm 43 operatively engages a worm gear 45, serving in turn, to actuate a vertical shaft 46, which may, of itself,

constitute a reel member, or which, if desired, may be provided with auxiliary winding surfaces (not shown) to receive, in spaced relation along the shaft 46, cables 21 and 28. Anchorage of the cables may be effected through screws 41, extended through the respective bight portions of the paired cables 21 and 28, at spaced points along shaft 46. The power unit may be provided with cable rollers or pulleys 48, preferably located at opposite ends of the assembly 30, the rollers 48 being particularly desirable where it is necessary to change the direction of the cables at these points. The reel shaft 46 may conveniently be journalled in decks 31 and 38, and, as preferred, a third deck structure 49 may serve to receive the shaft 46 in journaling relation thereto, and serve as a support for the worm gear 45, engaging particularly the hub portion 50 thereof.

The worm 43 and gear 45 may, together with other parts as desired, be enclosed in an oil-containing casing, omitted from the drawings for clearness. By this provision dust and moisture are excluded from the mechanism, and regular lubricating attention is obviated.

Due to the irreversible characteristic of a worm drive, in case of failure of the power source, it may be desirable to provide for manual operation of the doors, by relieving the worm gear 45 of operative association with the shaft 46. This is accomplished in the present example, through a clutch pin 5|, spring-pressed into a socket 52 in the hub 50, and projecting upwardly or outwardly of a collar 53 which is pinned as at 54, to the shaft, 46. A lifting lever 55 is pivoted, as shown, to the end of plunger 5|, and provided adjacent thereto with a cam portion 56. It will appear that, upon lifting the free end of lever 55 to a substantially vertical position, the plunger 5| will be withdrawn from the socket 52, and the shaft 46 permitted to rotate free of the gear 45, which will be held against manual rotation, by the worm 43.

Since a swinging door may. when in use, encounter a variety 'of obstructions to free movement, I prefer to provide an overload release switch 5! (see Fig. 7). As to structure, this switch includes a pair of fixed abutments 58 secured to the base 31 (Fig. 1). Mounted between the abutments, in opposed relation. are a pair of relatively heavy compression springs 59, the inner ends of which bear against opposed hingedly mounted blocks of insulation 66. The blocks are provided on their inner mating faces with companion contacts 6|. Through set screws 62, provision is made for adjusting the loading of springs 59. The blocks 60 are provided, as shown, each with an upwardly projecting roller 63. These rollers are spaced a substantial distance so as to receive therebetween, a collar 64, carried by the worm shaft 42.

The circuit relation of the switch identified with the switch points 6|, will appear from the wiring diagram of Fig. 10, in which it is seen that, being located in circuit just ahead of the mains or feeders, opening of this switch under any conditions will serve to stop the motor 40. The telescoping connection at the motor end of shaft 42 and the loading of springs 59, is such that the normal end thrust of shaft 42 in either direction, is insufficient to break the circuit through contacts 6|. When, however, due .to any abnormal loading of shaft 46 and worm gear 45, the thrust of shaft 42 becomes excessive, the resulting end- .wise movement of collar 64, will cause one of the blocks 60 to swing sufficiently to break the circuit through contacts 6|. It is to be noted that it is impossible for either of these insulating blocks 60, to follow the other block during the safety operation of the switch. This is due to the fact that the lower edge or end of each block 60 firmly abuts the base or deck 31 by, which the blocks are carried.

While it is possible to limit the operation of the motor in each direction of its rotation through suitable limit switches, installed, for example, on the door frame or other stationary portions of the structure, it is my preference to locate the several limit switches and the reversing switch hereinafter described, in a compact switching assembly carried by and forming a part of the operating unit 30. In this connection attention is directed to Figs. 5 and 8. A switch housing 65 may be carried in depending relation as shown, by the deck 38 of the driving unit 30. According to the example shown the housing 65 serves to contain the mechanism of three switches, viz., a self-closing toggle switch 66, which is in closed position when its operating lever extends to the right, Figs. 5 and 8; a selfclosing toggle switch 51 which is in closed position when its operating handle projects to the left, Figs. 5 and 8. Each of theswitches 66 and 61 may be of single pole, single throw toggle or snap-switch type, a number of suitable forms of which are available to the trade. Disposed somewhat near the opposite end of the housing 65, is a double pole, double throw switch, preferably of toggle type, and indicated at 68.

Actuation of the switches 66, 61 and 68 is effected in proper sequence, by means of a pair of reciprocable plungers or rods 69 and 10, supported, for endwise sliding movement, in a pair of apertured brackets H (Fig. 8) through which the plungers are movable within predetermined limits. The plunger 69, as appears from Fig. 8, consists preferably of a plurality of aligned, telescoping sections, the central section of the plunger serving to carry a pair of springs and a switchactuating block, hereinafter described. The manner of operative actuation of plunger 69 is sewn in Fig. 1, wherein it appears that as the door I? approaches and attains its closed position, the plunger 69 will be moved inwardly of the driving unit 30, or to the right (Fig. 8). When the door ii is moved outwardly and ap proaches and attains its outermost position, the pivot pin 23 associated with door I1, ,will operatively engage a projecting arm 12, on the plunger 69, to move the plunger oppositely toward its outermost position.

Since it will appear that the switching assembly may be disposed in a variety of positions relative to the driving unit 30, and since the projection 12 may be adjustably disposed in any position, near either end of the plunger 69, it will be obvious that this arrangement may be adaptcd, with only minor changes, to the arrangement of doors prevailing in Fig. 2.

As an auxiliary or independent means of actuating the switching assembly responsively to different positions of the doors, the cables 21 or 28, or both thereof, may be provided with suitable metallic projections 12 so located as to abut an eye member 13, and thus, when the cables attain predetermined positions, serve to actuate the switch assembly, through engagement of the projections with the sides of the eye member. This arrangement is preferred in connection with the structure of Figs. 3 and 4, and may be utilized in the arrangement shown in Fig. 2.

The switch assembly, shown separately in Fig. 8, is preferably disposed below and lengthwise of the operating unit 30, in such manner that the plunger 69 is moved to the right (Fig. 8), for example as the door ll attains its closed position. As above noted, the opposite movement of plunger G9 is effected upon impingement of arm 12 by the pivot pin23, (Fig. 1), when the door is slightly in advance of its open position. A movable block 14 is adjustably secured as by a set screw 15, to the central section of plunger 69. This block is, however, free to move along, and to a certain extent independently of the plunger 10. At the side of the block M are disposed spacer elements through the corresponding apertured ends of which the central section of plunger 69 is free to move, the opposite corresponding ends of the spacers being pinned or otherwise secured to the plunger 10. On opposite sides of the block H, and carried by the central part of plunger 69, are a pair of springs 16, disposed in opposed relation and thus tending to maintain the block 14 in a neutral position between the spacers. As shown, both of the plungers 69 and 10 are movably supported in the spacer blocks Ii.

When the block M is in its door-open position, as applied to Fig. 1, it will appear from Fig. 8 that it engages the self-closing toggle switch 66, in a manner to keep this switch open. When, however, the block 14 is at the opposite extreme of its range of movement, it will appear that its engagement with the switch lever 61, serves to hold the latter limit switch in its open position. As the block H is moved to a substantial extent in either direction from its central or neutral position, it operates through one of the springs I6, and the spacer abutted thereby, to actuate plunger 10 in a direction to change the setting of the double-throw reversing switch 68, this action being effected through the spaced pins H, each engaging one of the opposite sides of the lever of switch B8.' By this expedient, when the doors are brought to fully open position, and the plunger 69 moves farthest to the left (Fig. 8), the reversing switch 68 is appropriately positioned for the ensuing door-closing movement. Conversely, when the plunger 69 is moved farthest to the right, i. e., when the doors are closed, the reversing switch 68 is then appropriately positioned for the next door-opening movement of the operating unit, all of which fully appears when considering the structural arrangement in connection with the circuit diagram of Fig. 10.

The-circuit relation prevailing between the several limit switches, the reversing switch, as well as the motor, is thought to appear fully from Fig. 10, but may be discussed for sake of completeness, as follows: The motor employed may be any of the usual, standard types available to the trade. If of A. C. type, a fractional horsepower, repulsion-induction motor is preferred. It is understood that, in this type of motor, as the switch 68 is thrown in its opposite positions, the direction of initial current input will be reversed, and that the direction of initial input to motors of this type, will determine the direction of their running rotation.

Referring to Fig. 10 it is seen that one of the legs 18 has, interposed in one of its branches, both of the switches 66 and 61. The feeder circuit is shown as divided, and in one of the legs or divisions of this circuit such as 19, is disposed a switch 80 which may conveniently be located so that, when opened, it serves to deenergize the entire assembly. Since only one of the limit switches 66 and 81 is always closed, the other remaining open, when the unit is at rest, switch 88 when located remotely, and kept open, serves effectively to look a garage or other structure with which the power operator is associated.

For purposes of remote operation of the device, a switch 8| may be provided, and which may consist of a push button or other self-opening switch disposed, for example, in the house. As a means of still further remote control by completion of the motor operating circuit through the legs '19, a switch 82 may conveniently be mounted as on a drive way post (not shown), in a position to be accessible to the operator of a vehicle, and thus permit door-opening movement without requiring the driver to dismount.

As a still further auxiliary expedient to facilitate remote switching control of the motor unit, a vehicle-actuated switch 83 may be provided. A presently preferred form of switch for use in this location, is shown in detail in Fig. 11, which will be hereinafter described.

An added convenience of the assembly de scribed, consists in the provision of a light 92, so arranged in circuit (Fig. 10) that when the doors are open, the limit switch 61 being closed, the light 82 will be energized. Thus, at night, upon remotely starting the power operating unit to open the doors, the driveway and garage are illuminated until the doors are again closed, and switch 6'! opened by the action of member 14.

From the circuit arrangement illustrated in Fig. 10, it will appear that when switch is closed, closing any one of the switches 8|, 82 or 83, or any plurality thereof, will serve to close this side of the circuit, through the leads 79. It is understood, of course, that the reversing switch 68 is always appropriately positioned for the ensuing door action, through the coaction of plungers 69 and 18, as influenced by the doors themselves.

My present preference is to employ, as the tension element 21 and 28, airplane control cable, or a similar highly flexible and durable material of substantial tensile strength. Obviously, other forms of cable, rope, strap material or any of their equivalents may be employed. Since steel cable in short lengths does not exhibit any appreciable stretch, I prefer the arrangement of limit switches and reversing switches, as shown. When, however, there is employed a flexible tension member capable of any substantial stretch in normal use, it will appear that, as the doors attain or approach either their fully closed or fully open positions, the safety release switch 51 may be employed in lieu of the limit switches 66 and 61. When thus utilized, the safety switch 51 would be disposed in the circuit of Fig. 10, in lieu of the switches 65 and 61.

The switch structure I have proposed to be employed for actuation by the wheel of a vehicle such as an automobile, is shown in Fig. 11. The structure is indicated generally at 83, and consists of lower and upper telescoping housings indicated respectively as 84 and 85. The housings are preferably of substantial length and preferably operate in telescoping relation so that as a wheel of a car runs over the enclosure, the portion 85 thereof, is depressed. This movement is opposed by a pair of compression springs 86, disposed in spaced relation endwise of the switch structure. Upward movement of housing portion 85, under influence of springs 86, may be 0pposed and limited as by headed studs 8! extended through apertured leg portions 88, secured to the inside surface of the upper housing portion 85.

The switch mechanism, of which there are preferably a plurality, so as to avoid a critical point of actuation of the switch, may consist of any suitable self-opening type of switch mechanism, for example, an exceptionally rugged pushbutton switch. Toggle or snap switch mechanism of self-opening type, may obviously be employed in lieu of the push-button structures indicated generally at 89. Each of the switches is preferably characterized by an upstanding operating stud or lever 98, each of which is engaged by a compression spring 91, the opposite ends of these springs being engaged in turn, by the under surface of the upper housing portion 85. The circuit relation of these switches is shown diagrammatically as at 83, in Fig. 10.

In operation, it will appear that, as soon as any one of the vehicle wheels is brought to bear upon the upper housing portion 85, one or more of the switch mechanisms 89 will be actuated toward closed position, thus completing one leg of the energizing circuit. The reversing switch 68, having previously been brought to one or the other of its closed positions, the motor of the power operator will actuate the doors in the direction intended. If operation of the doors takes place in the direction opposite to that desired, it is merely necessary to repeat the actuation of switch 83, through one of the mechanisms 89, until the power operator again cycles completely, and the doors are permitted to remain in the desired position or condition.

The switch 83 is preferably so constructed that the housing 84 and 85, fit snugly together so as to exclude moisture from the casing. The exterior surfaces of the' housing portion may be waterproofed by suitable known expedients and, as may be desired, the switch mechanisms 89 may be fully enclosed and waterproof cable be employed as an underground connection to the structure.

To summarize the operation of the device as a whole, by way of example with respect to the structure as shown in Fig. 1, it will be understood that when the doors are in fully closed position, the plunger 69 is in its right hand position (Fig. 8). The limit switch 61 is then open and the reversing switch 68 so positioned that the initial movement of the motor is in a direction to put the cables 21 under tension, and correspondingly to pay out the cables 28, all as will fully appear from the arrangement of cables as wound upon the shaft or reel member 46 (Figs. 5 and 6). The switch 61 being open, the path of the current will be through leads I9 and one of the switches8l, 82 or 83, or a plurality of such switches. As the cables 21 are wound upon the reel 48, pin 23 will be drawn toward the door opening, until the one thereof associated with door ll, engages projection 12, again moving plunger 69 to the left (Fig. 8). Door opening.

movement being completed at this time, the block '14 will engage switch 66 to bring it toward open position, and the self-closing switch 51 will be permitted to close. It will be noted that, ex- 'cept at the beginning and end of the door closing movement, both of switches 66 and 81 will be in closed position and thus the motor will be energized through lead 18, directly to the reversing switch 68, it being necessary only to close one of the self-opening switches 8|, 82 or 83, for a period of a very few seconds to initiate the action of the motor.

The legs 19 of the circuit thus being open, when door opening movement is completed, the opening of limit switch 66, will deenergize the motor. It will be observed that, concurrently with the opening of switch 66, the reversing switch 68 will have been altered in position, so as to reverse the motor rotation, upon its subsequent re-energization for door-closing movement. As soon then, as any one of the switches 8!, 82 or 83 is again actuated, resumed rotation of the motor will rotate shaft 46 in the opposite direction or so as to pay out cable 21, and correspondingly tension and wrap the cable 28. As this operation continues, both limit switches 66 and 61 remain closed until plunger 69 is abuttingly engaged by the door I! and moved to the right (Fig. 8), so that block 14 is brought to bear against the lever of switch 61, opening this switch. The reversing switch 68 is again thrown, ready for a repetition of the cycle.

From the arrangement of switches in the circuit of Fig. 10, it is seen that any desired opera tion of the doors, whether opening movement or closing movement thereof, is obtainable at any time, from any of the remote control stations, at which may be located any of the switches 8|, 82 or 83.

It appears from the foregoing description that since limiting of operation of the power unit may be accomplished entirely by the plunger 68, mounted in the path of the door, the power unit, per se, is completely self-contained, except for the current source. Since the various cables 21 and 28, the arms 22 and 24, where necessary to be used, are all easily and quickly installed by anyone without particular skill, the cost of erection work is minimized. In the event the power unit or operator requires servicing of any nature, it may be removed and sent to a convenient place of repair, without seriously disturbing the mechanical and 'cable connections to the doors.

The device of my invention is of simple and rugged construction, may be formed almost entirely of stock materials and a minimum of wiring is necessary apart from that internal to or associated with, the power operator unit. In this manner installation expense is minimized, hazards of local installation are reduced, and operation of the device is assuredly uniform. It {will further appear that breakage of doors or operative connections, due to unforeseen obstructions, is obviated entirely by the provision of the safety relief switch and that the device otherwise at tains, in all respects, each of the several objects more fully set out above.

While the invention has been described by making particular and specific reference to a form thereof presently preferred by me, it is to be understood that a number of changes may be made in the parts, their combinations and arrangement, without departing from the spirit and full intended scope of the invention, as defined by the appended claims.

I claim as my invention:

1. In combination with a building and doors pivotally mounted to swing outwardly from said building, an electric power operator unit within the building, and near the door opening, cables actuatedby the operating unit, means confining each cable to a path of movement toward and away from the doors and door opening, and a pair of pivoted arms serving as connections between the cables and each of the doors, one of said arms being pivotally carried by the associated door, and the other arm pivotally mounted within the building, said arms being adapted, upon actuation of the cables in one direction, to cause a swinging movement of the doors away from the building and toward open position, switching means carried by the operator unit including a switch-actuating plunger and an arm on the plunger, the plunger and arm being disposed for selective engagement by door-carried elements.

2. In combination, a building structure, outwardly swinging doors therefor, a power operator Within the structure, cables arranged for actuation by the operator in a substantially horizontal plane within the structure, means providing paths of movement of the cables toward and away from the door opening, a pair of distance arms for each door, one of which is pivotally carried by said door and the other by a side wall of the building at corresponding ends of the arms, and pivotally connected at their opposite corresponding ends, to each other and to said cables.

3. In combination, a building, a door therefor, a power operator for the door including a reel member, cables arranged to be actuated by the reel member, a pair of pivotally connected arms, a connection from said cables to said arms, each of said arms having a pivot remote from its point of connection to the cable, and each having a pivot anchorage, characterized by a plurality of spaced pivot-receiving openings,vone of such anchorages being carried by the door to be operated and the other anchorage mounted in fixed position within the building.

4. In an automatic power door assembly, a power unit including a reel member, a cable connecting the reel member to the door to be operated thereby, a pair of cable pulleys at opposite ends of the cable, located to define a path of cable travel toward and away from the door opening, an electric motor, an assembly of limit switches carried by the power unit, an actuating arm common to a pair of said switches and including a plunger disposed to be engaged by the door to be operated, for controlling said switches.

5. An automatic power door assembly including a unitary door-operating device, a winding member therein for the operative reception of door-moving cables, a pair of cable elements movable by the winding member toward and away from the door opening, a motor, gearing between the motor and winding member, a base for the motor, gearing and winding member, a pair of limit switches and a reversing switch, constructed and carried as an enclosed unit by said base member, and a plunger so disposed as to be engaged by the door, and being in controlling relation to each of said switches.

6. An automatic power-door assembly including an electric driving unit comprising a motor, a reel member for the reception of door-operating cables, and actuated by said motor, a base common to said motor and reel member, cable pulleys carried by said base, a motor-switching unit carried by the base and comprising separate switches for limiting the operation of the motor in each of its directions of rotation, together with a reversing switch, and a door-operated plunger disposed for engagement by an associated door, and arranged, upon engagement, for conjointly actuating one of said limit switches and the reversing switch.

7. An electric operating device for doors, in cluding paired endless cables, one for each door, a distance arm connecting each cable to the door,

and pivotally engaging the door, a driving unit comprising a base, a motor, gearing including a worm driven by said motor, and a worm gear, the gearing being mounted upon said base, a power reel on which the door-operating cables are wound, the reel being carried by the base and actuated by said gearing, a switch housing arranged in depending relation to said base, a motor-reversing switch, limit switching means carried within said housing, a door-operated plunger arranged for movement endwise of said switch housing, and adapted sequentially to actuate said switches, responsively to door position, and a motor overload switch operable independently of the switches aforesaid, and movable responsively to worm torque, to stop said motor.

8. In a device for operating swinging doors, a power reel unit, a cable actuated by the reel unit, a cable pulley mounted within the building remote from the door opening, a pulley carried by the power unit near the door opening, a pair of arms pivotally connected to each other, and pivoted, respectively, to the door, and at a point within the building inwardly of the door, the opposite ends of the arms being connected to the cable, and brackets carried by the door and inner wall of the building, forming a plurality of pivots seats for each of said arms, so as to permit adjustment of the angularity of the arms and range of door movement.

9. In combination with a swinging door, a structure closed thereby, a power door operator constructed as a unitary electric driving and switching unit including a motor and a power reel, a door-actuating cable wound on said reel, said unit including a motor reversing switch and limit switches, a plunger projecting from the unit into the path of the door, for actuating the switches, a distance arm serving as a connection from the cable to the door, and a switch-actuating arm in'the path of the said connection.

LEO H. GROSS. 

